10:00 AM - 10:15 AM
▼ [13a-S302-5] Colossal enhancement of spin-caloritronic unidirectional magnetoresistance in a Weyl ferromagnet at room temperature
Keywords:unidirectional magneto resistance, spin-caloritronics, anomalous nernst effect
Unidirectional magnetoresistance (UMR) is a novel spintronic feature in nano-science, which has been intensively studied in hopes of realizing all-electrical magnetization direction detection devices. However, cryogenic temperatures and/or high magnetic fields have been required to achieve noticeable effects. Here, we exploit the high heat-to-charge conversion efficiency of the Heusler alloy Weyl semimetal Co2MnGa to produce a two orders of magnitude enhancement of the room temperature UMR ratio, when compared with conventional ferromagnets. We reveal that Joule-heating-originated vertical thermal gradients, combined with the large anomalous Nernst effect in this topologically-non-trivial material, converge into the manifestation of a strong UMR in nano-scaled wires. Our results open up new horizons of using thermoelectric voltages in novel materials for magnetization direction detection.